1,720,954 research outputs found
All-optical multi-level phase quantization based on phase sensitive amplification with low-order harmonics
No full textA novel scheme is proposed for all-optical multi-level phase quantization by mixing two lower-order harmonics, rather than mixing the signal with its conjugate (M−1)th harmonic, which is difficult to be generated but necessary for the traditional quantization method. The low-order harmonics used in the proposed scheme are determined as the conjugate (M/2−1)th and the (M/2+1)thharmonics for M=4n , or the conjugate (M/2−2)th and the (M/2+2)th harmonics for M=4n+2, or the conjugate [(M−1)/2]th and the [(M+1)/2]th harmonics for M=2n+1, n=1,2,3…The simulations show the effectiveness of the scheme for the eight- and nine-level all-optical phase quantization. Furthermore, the application of the scheme to the all-optical phase regeneration is validated. An improved method with two cascading stages is also proposed and validated to achieve a monotonic step-like phase–phase transfer characteristic for the optimized all-optical phase quantization. This proposed scheme provides a new way for multi-level phase quantization and multi-level phase shift keying regeneration to meet the ever increasing demand for the bandwidth in fiber optic communications
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dynamic decision-making under uncertainties: algorithms based on linear decision rules and applications in operating models
Full text linkThis thesis is to propose efficient and robust algorithms based on Linear
Decision Rule (LDR), which expand the applicability of the existing LDR methods. Representative and complex operation models are analyzed and solved by the proposed approaches. The research motivation and scope are provided in Chapter 1.
Chapter 2 introduces the generic LDR method and the contributions of this thesis to the LDR literature. To extend the LDR method to nonlinear objectives, two methods are proposed. The first is an iterative LDR (ILDR) method that tackles general concave differentiable nonlinear terms in the objective function. The second treats quadratic terms in the objective function by a Second-Order Cone approximation. The details and implementation of the proposed methods are presented in Chapter 3 and Chapter 4.
Chapter 3 utilizes the Robust Optimization approach to derive an ILDR solution for a multi-period hydropower generation problem that has a nonlinear objective function. The methodology results in tractable second-order cone formulations. The performance of the ILDR approach is compared with the Sampling Stochastic Dynamic Programming (SSDP) policy derived using historical data.
In Chapter 4, a joint pricing and inventory control problem of a perishable product with a fixed lifetime is analyzed. Both the backlogging and lost-sales cases are discussed. The analytic results shed new light on perishable inventory management, and the proposed approach provides a significantly simpler proof of a classical structural result in the literature. Two heuristics were proposed, one of which is a modification and improvement of an existing heuristic. The other one is an LDR based approach, which approximates the dynamics and the objective function by robust counterparts. The robust counterpart for the backlogging case is tight, and it leads to a satisfactory performance of less than 1% loss of optimality. Although the robust counterpart for the lost-sales case is not tight in the current numerical study, the gap between the LDR method and the SDP benchmark is less than 5% on average.
Chapter 5 summarizes the contributions of the thesis and discusses about potential improvements. One important working project, an approximate dynamic programming based on LDR (ADP-LDR) approach, is introduced for future research.Item withdrawn by Mark Zulauf ([email protected]) on 2014-07-15T19:03:57Z
Item was in collections:
University of Illinois Theses & Dissertations (ID: 1)
No. of bitstreams: 1
Pan_Limeng.pdf: 3710512 bytes, checksum: a550d4ddf3ba0f3e05b73719f81aed9c (MD5)Made available in DSpace on 2014-09-16T17:12:29Z (GMT). No. of bitstreams: 2
Limeng_Pan.pdf: 3710512 bytes, checksum: a550d4ddf3ba0f3e05b73719f81aed9c (MD5)
license.txt: 4057 bytes, checksum: d3a1d5dbf24617f5425b7ad86f75c7f5 (MD5)Embargo set by: Seth Robbins for item 50500
Lift date: 2016-09-16T17:13:01Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 50500 on 2016-09-22T20:59:22Z
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
